Reborn is the name of the achievement and this one is definitely story-related.
All you have to do is go through your first dungeon and complete it successfully, which shouldn't be too bad on any of the difficulties, even on Hard. None of the enemies inside are powerful enough to stop you and you'll earn good equipment to withstand any punishment from their assaults. Once you defeat the rock troll and his two guards and exit the Well Of Souls, the achievement should unlock. It's really simple! Have fun and good luck!